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This section of the archives stores flipcode's complete Developer Toolbox collection, featuring a variety of mini-articles and source code contributions from our readers.

 

  XML Parser
  Submitted by



XML is hyped enough to promote it,but i`ll say anyway, XML is cool :) Human readable, hierarchical and well defined, which makes it perfect choose for storing and retrieving of complex structural data where speed is not a primary concern, like storing the user profiles, in game configurations etc... The only annoying problem is that standart XML packages are mostly platform dependend.

But for our mostly simple needs we dont need all xml features like namespaces or DTD. There are too approaches for reading XML one is calling callback for every node read from the XML, fastest but imho cumbersome way to read xml, second one is what MSoft calls DOM (Document object model) where whole XML tree parsed and loaded in memory, slower and waste memory for really big XMLs but tons easier to use.

I used Expat open source project (http://sourceforge.net/projects/expat) to actually parse XML because its really fast, and multiplatform. But expat uses callback method to parse xml, so i've builded a wraper around it. In the heart of the wrapper is the XmlNodeRef class which is a smart pointer to the XmlNode class, and takes care of the memory managment issues. After parsing XML, parser return XML hieararchy thru XmlNodeRef (smart pointer) of root node. By iterating on child nodes with getChildCount()/getChild(index) you can traverse whole xml hierarchy.

To read Xml:

XmlParser xml;
XmlNodeRef root = xml.parse( "test.xml" );
if (root) { // Test if root non null.
  String rootTag = root-getTag();
  // Browse root childs.
  for (int i = 0; i < root-getChildCount(); i++) {
    XmlNodeRef child = root-getChild(i);
    String childTag = child-getTag();
    String name = child-getAttribute("name");
  }
} 



To Write Xml file:

XmlNodeRef root( "ROOT" ); // Creates root node.
XmlNodeRef child1( "FirstChild" ); // Creates childs.
XmlNodeRef child2( "SecondChild" );
child1-SetAttribute( "name","First" );
child2-SetAttribute( "name","Second" );
root-AddChild( child1 );
root-AddChild( child2 );
String xml = root-getXML(); // String now contain xml tree. 





I'd really like to see any improvements/bug fixes/safety enforcements for this peace of code, and more use of XML. Enjoy it :)


Currently browsing [xml.zip] (66,316 bytes) - [expat.h] - (26,371 bytes)

/*
Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
See the file COPYING for copying permission.
*/

#ifndef XmlParse_INCLUDED #define XmlParse_INCLUDED 1

#include <stdlib.h>

#ifndef XMLPARSEAPI # ifdef __declspec # define XMLPARSEAPI __declspec(dllimport) # else # define XMLPARSEAPI /* nothing */ # endif #endif /* not defined XMLPARSEAPI */

#ifdef __cplusplus extern "C" { #endif

typedef void *XML_Parser;

/* Information is UTF-8 encoded. */ typedef char XML_Char; typedef char XML_LChar;

enum XML_Content_Type { XML_CTYPE_EMPTY = 1, XML_CTYPE_ANY, XML_CTYPE_MIXED, XML_CTYPE_NAME, XML_CTYPE_CHOICE, XML_CTYPE_SEQ };

enum XML_Content_Quant { XML_CQUANT_NONE, XML_CQUANT_OPT, XML_CQUANT_REP, XML_CQUANT_PLUS };

/* If type == XML_CTYPE_EMPTY or XML_CTYPE_ANY, then quant will be XML_CQUANT_NONE, and the other fields will be zero or NULL. If type == XML_CTYPE_MIXED, then quant will be NONE or REP and numchildren will contain number of elements that may be mixed in and children point to an array of XML_Content cells that will be all of XML_CTYPE_NAME type with no quantification.

If type == XML_CTYPE_NAME, then the name points to the name, and the numchildren field will be zero and children will be NULL. The quant fields indicates any quantifiers placed on the name.

CHOICE and SEQ will have name NULL, the number of children in numchildren and children will point, recursively, to an array of XML_Content cells.

The EMPTY, ANY, and MIXED types will only occur at top level. */


typedef struct XML_cp XML_Content;

struct XML_cp { enum XML_Content_Type type; enum XML_Content_Quant quant; const XML_Char * name; unsigned int numchildren; XML_Content * children; };

/* This is called for an element declaration. See above for description of the model argument. It's the caller's responsibility to free model when finished with it. */

typedef void (*XML_ElementDeclHandler) (void *userData, const XML_Char *name, XML_Content *model);

void XMLPARSEAPI XML_SetElementDeclHandler(XML_Parser parser, XML_ElementDeclHandler eldecl);

/* The Attlist declaration handler is called for *each* attribute. So a single Attlist declaration with multiple attributes declared will generate multiple calls to this handler. The "default" parameter may be NULL in the case of the "#IMPLIED" or "#REQUIRED" keyword. The "isrequired" parameter will be true and the default value will be NULL in the case of "#REQUIRED". If "isrequired" is true and default is non-NULL, then this is a "#FIXED" default. */

typedef void (*XML_AttlistDeclHandler) (void *userData, const XML_Char *elname, const XML_Char *attname, const XML_Char *att_type, const XML_Char *dflt, int isrequired);

void XMLPARSEAPI XML_SetAttlistDeclHandler(XML_Parser parser, XML_AttlistDeclHandler attdecl);

/* The XML declaration handler is called for *both* XML declarations and text declarations. The way to distinguish is that the version parameter will be null for text declarations. The encoding parameter may be null for XML declarations. The standalone parameter will be -1, 0, or 1 indicating respectively that there was no standalone parameter in the declaration, that it was given as no, or that it was given as yes. */

typedef void (*XML_XmlDeclHandler) (void *userData, const XML_Char *version, const XML_Char *encoding, int standalone);

void XMLPARSEAPI XML_SetXmlDeclHandler(XML_Parser parser, XML_XmlDeclHandler xmldecl);

typedef struct { void *(*malloc_fcn)(size_t size); void *(*realloc_fcn)(void *ptr, size_t size); void (*free_fcn)(void *ptr); } XML_Memory_Handling_Suite;

/* Constructs a new parser; encoding is the encoding specified by the external protocol or null if there is none specified. */

XML_Parser XMLPARSEAPI XML_ParserCreate(const XML_Char *encoding);

/* Constructs a new parser and namespace processor. Element type names and attribute names that belong to a namespace will be expanded; unprefixed attribute names are never expanded; unprefixed element type names are expanded only if there is a default namespace. The expanded name is the concatenation of the namespace URI, the namespace separator character, and the local part of the name. If the namespace separator is '\0' then the namespace URI and the local part will be concatenated without any separator. When a namespace is not declared, the name and prefix will be passed through without expansion. */

XML_Parser XMLPARSEAPI XML_ParserCreateNS(const XML_Char *encoding, XML_Char namespaceSeparator);

/* Constructs a new parser using the memory management suit referred to by memsuite. If memsuite is NULL, then use the standard library memory suite. If namespaceSeparator is non-NULL it creates a parser with namespace processing as described above. The character pointed at will serve as the namespace separator.

All further memory operations used for the created parser will come from the given suite. */


XML_Parser XMLPARSEAPI XML_ParserCreate_MM(const XML_Char *encoding, const XML_Memory_Handling_Suite *memsuite, const XML_Char *namespaceSeparator);

/* atts is array of name/value pairs, terminated by 0; names and values are 0 terminated. */

typedef void (*XML_StartElementHandler)(void *userData, const XML_Char *name, const XML_Char **atts);

typedef void (*XML_EndElementHandler)(void *userData, const XML_Char *name);

/* s is not 0 terminated. */ typedef void (*XML_CharacterDataHandler)(void *userData, const XML_Char *s, int len);

/* target and data are 0 terminated */ typedef void (*XML_ProcessingInstructionHandler)(void *userData, const XML_Char *target, const XML_Char *data);

/* data is 0 terminated */ typedef void (*XML_CommentHandler)(void *userData, const XML_Char *data);

typedef void (*XML_StartCdataSectionHandler)(void *userData); typedef void (*XML_EndCdataSectionHandler)(void *userData);

/* This is called for any characters in the XML document for which there is no applicable handler. This includes both characters that are part of markup which is of a kind that is not reported (comments, markup declarations), or characters that are part of a construct which could be reported but for which no handler has been supplied. The characters are passed exactly as they were in the XML document except that they will be encoded in UTF-8. Line boundaries are not normalized. Note that a byte order mark character is not passed to the default handler. There are no guarantees about how characters are divided between calls to the default handler: for example, a comment might be split between multiple calls. */

typedef void (*XML_DefaultHandler)(void *userData, const XML_Char *s, int len);

/* This is called for the start of the DOCTYPE declaration, before any DTD or internal subset is parsed. */

typedef void (*XML_StartDoctypeDeclHandler)(void *userData, const XML_Char *doctypeName, const XML_Char *sysid, const XML_Char *pubid, int has_internal_subset );

/* This is called for the start of the DOCTYPE declaration when the closing > is encountered, but after processing any external subset. */ typedef void (*XML_EndDoctypeDeclHandler)(void *userData);

/* This is called for entity declarations. The is_parameter_entity argument will be non-zero if the entity is a parameter entity, zero otherwise.

For internal entities (<!ENTITY foo "bar">), value will be non-null and systemId, publicID, and notationName will be null. The value string is NOT null terminated; the length is provided in the value_length argument. Since it is legal to have zero-length values, do not use this argument to test for internal entities.

For external entities, value will be null and systemId will be non-null. The publicId argument will be null unless a public identifier was provided. The notationName argument will have a non-null value only for unparsed entity declarations. */


typedef void (*XML_EntityDeclHandler) (void *userData, const XML_Char *entityName, int is_parameter_entity, const XML_Char *value, int value_length, const XML_Char *base, const XML_Char *systemId, const XML_Char *publicId, const XML_Char *notationName); void XMLPARSEAPI XML_SetEntityDeclHandler(XML_Parser parser, XML_EntityDeclHandler handler);

/* OBSOLETE -- OBSOLETE -- OBSOLETE This handler has been superceded by the EntityDeclHandler above. It is provided here for backward compatibility. This is called for a declaration of an unparsed (NDATA) entity. The base argument is whatever was set by XML_SetBase. The entityName, systemId and notationName arguments will never be null. The other arguments may be. */

typedef void (*XML_UnparsedEntityDeclHandler)(void *userData, const XML_Char *entityName, const XML_Char *base, const XML_Char *systemId, const XML_Char *publicId, const XML_Char *notationName);

/* This is called for a declaration of notation. The base argument is whatever was set by XML_SetBase. The notationName will never be null. The other arguments can be. */

typedef void (*XML_NotationDeclHandler)(void *userData, const XML_Char *notationName, const XML_Char *base, const XML_Char *systemId, const XML_Char *publicId);

/* When namespace processing is enabled, these are called once for each namespace declaration. The call to the start and end element handlers occur between the calls to the start and end namespace declaration handlers. For an xmlns attribute, prefix will be null. For an xmlns="" attribute, uri will be null. */

typedef void (*XML_StartNamespaceDeclHandler)(void *userData, const XML_Char *prefix, const XML_Char *uri);

typedef void (*XML_EndNamespaceDeclHandler)(void *userData, const XML_Char *prefix);

/* This is called if the document is not standalone (it has an external subset or a reference to a parameter entity, but does not have standalone="yes"). If this handler returns 0, then processing will not continue, and the parser will return a XML_ERROR_NOT_STANDALONE error. */

typedef int (*XML_NotStandaloneHandler)(void *userData);

/* This is called for a reference to an external parsed general entity. The referenced entity is not automatically parsed. The application can parse it immediately or later using XML_ExternalEntityParserCreate. The parser argument is the parser parsing the entity containing the reference; it can be passed as the parser argument to XML_ExternalEntityParserCreate. The systemId argument is the system identifier as specified in the entity declaration; it will not be null. The base argument is the system identifier that should be used as the base for resolving systemId if systemId was relative; this is set by XML_SetBase; it may be null. The publicId argument is the public identifier as specified in the entity declaration, or null if none was specified; the whitespace in the public identifier will have been normalized as required by the XML spec. The context argument specifies the parsing context in the format expected by the context argument to XML_ExternalEntityParserCreate; context is valid only until the handler returns, so if the referenced entity is to be parsed later, it must be copied. The handler should return 0 if processing should not continue because of a fatal error in the handling of the external entity. In this case the calling parser will return an XML_ERROR_EXTERNAL_ENTITY_HANDLING error. Note that unlike other handlers the first argument is the parser, not userData. */

typedef int (*XML_ExternalEntityRefHandler)(XML_Parser parser, const XML_Char *context, const XML_Char *base, const XML_Char *systemId, const XML_Char *publicId);

/* This structure is filled in by the XML_UnknownEncodingHandler to provide information to the parser about encodings that are unknown to the parser. The map[b] member gives information about byte sequences whose first byte is b. If map[b] is c where c is >= 0, then b by itself encodes the Unicode scalar value c. If map[b] is -1, then the byte sequence is malformed. If map[b] is -n, where n >= 2, then b is the first byte of an n-byte sequence that encodes a single Unicode scalar value. The data member will be passed as the first argument to the convert function. The convert function is used to convert multibyte sequences; s will point to a n-byte sequence where map[(unsigned char)*s] == -n. The convert function must return the Unicode scalar value represented by this byte sequence or -1 if the byte sequence is malformed. The convert function may be null if the encoding is a single-byte encoding, that is if map[b] >= -1 for all bytes b. When the parser is finished with the encoding, then if release is not null, it will call release passing it the data member; once release has been called, the convert function will not be called again.

Expat places certain restrictions on the encodings that are supported using this mechanism.

1. Every ASCII character that can appear in a well-formed XML document, other than the characters

$@\^`{}~

must be represented by a single byte, and that byte must be the same byte that represents that character in ASCII.

2. No character may require more than 4 bytes to encode.

3. All characters encoded must have Unicode scalar values <= 0xFFFF, (ie characters that would be encoded by surrogates in UTF-16 are not allowed). Note that this restriction doesn't apply to the built-in support for UTF-8 and UTF-16.

4. No Unicode character may be encoded by more than one distinct sequence of bytes. */


typedef struct { int map[256]; void *data; int (*convert)(void *data, const char *s); void (*release)(void *data); } XML_Encoding;

/* This is called for an encoding that is unknown to the parser. The encodingHandlerData argument is that which was passed as the second argument to XML_SetUnknownEncodingHandler. The name argument gives the name of the encoding as specified in the encoding declaration. If the callback can provide information about the encoding, it must fill in the XML_Encoding structure, and return 1. Otherwise it must return 0. If info does not describe a suitable encoding, then the parser will return an XML_UNKNOWN_ENCODING error. */

typedef int (*XML_UnknownEncodingHandler)(void *encodingHandlerData, const XML_Char *name, XML_Encoding *info);

void XMLPARSEAPI XML_SetElementHandler(XML_Parser parser, XML_StartElementHandler start, XML_EndElementHandler end);

void XMLPARSEAPI XML_SetStartElementHandler(XML_Parser, XML_StartElementHandler);

void XMLPARSEAPI XML_SetEndElementHandler(XML_Parser, XML_EndElementHandler);

void XMLPARSEAPI XML_SetCharacterDataHandler(XML_Parser parser, XML_CharacterDataHandler handler);

void XMLPARSEAPI XML_SetProcessingInstructionHandler(XML_Parser parser, XML_ProcessingInstructionHandler handler); void XMLPARSEAPI XML_SetCommentHandler(XML_Parser parser, XML_CommentHandler handler);

void XMLPARSEAPI XML_SetCdataSectionHandler(XML_Parser parser, XML_StartCdataSectionHandler start, XML_EndCdataSectionHandler end);

void XMLPARSEAPI XML_SetStartCdataSectionHandler(XML_Parser parser, XML_StartCdataSectionHandler start);

void XMLPARSEAPI XML_SetEndCdataSectionHandler(XML_Parser parser, XML_EndCdataSectionHandler end);

/* This sets the default handler and also inhibits expansion of internal entities. The entity reference will be passed to the default handler. */

void XMLPARSEAPI XML_SetDefaultHandler(XML_Parser parser, XML_DefaultHandler handler);

/* This sets the default handler but does not inhibit expansion of internal entities. The entity reference will not be passed to the default handler. */

void XMLPARSEAPI XML_SetDefaultHandlerExpand(XML_Parser parser, XML_DefaultHandler handler);

void XMLPARSEAPI XML_SetDoctypeDeclHandler(XML_Parser parser, XML_StartDoctypeDeclHandler start, XML_EndDoctypeDeclHandler end);

void XMLPARSEAPI XML_SetStartDoctypeDeclHandler(XML_Parser parser, XML_StartDoctypeDeclHandler start);

void XMLPARSEAPI XML_SetEndDoctypeDeclHandler(XML_Parser parser, XML_EndDoctypeDeclHandler end);

void XMLPARSEAPI XML_SetUnparsedEntityDeclHandler(XML_Parser parser, XML_UnparsedEntityDeclHandler handler);

void XMLPARSEAPI XML_SetNotationDeclHandler(XML_Parser parser, XML_NotationDeclHandler handler);

void XMLPARSEAPI XML_SetNamespaceDeclHandler(XML_Parser parser, XML_StartNamespaceDeclHandler start, XML_EndNamespaceDeclHandler end);

void XMLPARSEAPI XML_SetStartNamespaceDeclHandler(XML_Parser parser, XML_StartNamespaceDeclHandler start);

void XMLPARSEAPI XML_SetEndNamespaceDeclHandler(XML_Parser parser, XML_EndNamespaceDeclHandler end);

void XMLPARSEAPI XML_SetNotStandaloneHandler(XML_Parser parser, XML_NotStandaloneHandler handler);

void XMLPARSEAPI XML_SetExternalEntityRefHandler(XML_Parser parser, XML_ExternalEntityRefHandler handler);

/* If a non-null value for arg is specified here, then it will be passed as the first argument to the external entity ref handler instead of the parser object. */ void XMLPARSEAPI XML_SetExternalEntityRefHandlerArg(XML_Parser, void *arg);

void XMLPARSEAPI XML_SetUnknownEncodingHandler(XML_Parser parser, XML_UnknownEncodingHandler handler, void *encodingHandlerData);

/* This can be called within a handler for a start element, end element, processing instruction or character data. It causes the corresponding markup to be passed to the default handler. */ void XML_DefaultCurrent(XML_Parser parser);

/* If do_nst is non-zero, and namespace processing is in effect, and a name has a prefix (i.e. an explicit namespace qualifier) then that name is returned as a triplet in a single string separated by the separator character specified when the parser was created: URI + sep + local_name + sep + prefix.

If do_nst is zero, then namespace information is returned in the default manner (URI + sep + local_name) whether or not the names has a prefix. */


void XMLPARSEAPI XML_SetReturnNSTriplet(XML_Parser parser, int do_nst);

/* This value is passed as the userData argument to callbacks. */ void XMLPARSEAPI XML_SetUserData(XML_Parser parser, void *userData);

/* Returns the last value set by XML_SetUserData or null. */ #define XML_GetUserData(parser) (*(void **)(parser))

/* This is equivalent to supplying an encoding argument to XML_ParserCreate. It must not be called after XML_Parse or XML_ParseBuffer. */

int XMLPARSEAPI XML_SetEncoding(XML_Parser parser, const XML_Char *encoding);

/* If this function is called, then the parser will be passed as the first argument to callbacks instead of userData. The userData will still be accessible using XML_GetUserData. */

void XMLPARSEAPI XML_UseParserAsHandlerArg(XML_Parser parser);

/* Sets the base to be used for resolving relative URIs in system identifiers in declarations. Resolving relative identifiers is left to the application: this value will be passed through as the base argument to the XML_ExternalEntityRefHandler, XML_NotationDeclHandler and XML_UnparsedEntityDeclHandler. The base argument will be copied. Returns zero if out of memory, non-zero otherwise. */

int XMLPARSEAPI XML_SetBase(XML_Parser parser, const XML_Char *base);

const XML_Char XMLPARSEAPI * XML_GetBase(XML_Parser parser);

/* Returns the number of the attribute/value pairs passed in last call to the XML_StartElementHandler that were specified in the start-tag rather than defaulted. Each attribute/value pair counts as 2; thus this correspondds to an index into the atts array passed to the XML_StartElementHandler. */

int XMLPARSEAPI XML_GetSpecifiedAttributeCount(XML_Parser parser);

/* Returns the index of the ID attribute passed in the last call to XML_StartElementHandler, or -1 if there is no ID attribute. Each attribute/value pair counts as 2; thus this correspondds to an index into the atts array passed to the XML_StartElementHandler. */

int XMLPARSEAPI XML_GetIdAttributeIndex(XML_Parser parser);

/* Parses some input. Returns 0 if a fatal error is detected. The last call to XML_Parse must have isFinal true; len may be zero for this call (or any other). */ int XMLPARSEAPI XML_Parse(XML_Parser parser, const char *s, int len, int isFinal);

void XMLPARSEAPI * XML_GetBuffer(XML_Parser parser, int len);

int XMLPARSEAPI XML_ParseBuffer(XML_Parser parser, int len, int isFinal);

/* Creates an XML_Parser object that can parse an external general entity; context is a '\0'-terminated string specifying the parse context; encoding is a '\0'-terminated string giving the name of the externally specified encoding, or null if there is no externally specified encoding. The context string consists of a sequence of tokens separated by formfeeds (\f); a token consisting of a name specifies that the general entity of the name is open; a token of the form prefix=uri specifies the namespace for a particular prefix; a token of the form =uri specifies the default namespace. This can be called at any point after the first call to an ExternalEntityRefHandler so longer as the parser has not yet been freed. The new parser is completely independent and may safely be used in a separate thread. The handlers and userData are initialized from the parser argument. Returns 0 if out of memory. Otherwise returns a new XML_Parser object. */ XML_Parser XMLPARSEAPI XML_ExternalEntityParserCreate(XML_Parser parser, const XML_Char *context, const XML_Char *encoding);

enum XML_ParamEntityParsing { XML_PARAM_ENTITY_PARSING_NEVER, XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE, XML_PARAM_ENTITY_PARSING_ALWAYS };

/* Controls parsing of parameter entities (including the external DTD subset). If parsing of parameter entities is enabled, then references to external parameter entities (including the external DTD subset) will be passed to the handler set with XML_SetExternalEntityRefHandler. The context passed will be 0. Unlike external general entities, external parameter entities can only be parsed synchronously. If the external parameter entity is to be parsed, it must be parsed during the call to the external entity ref handler: the complete sequence of XML_ExternalEntityParserCreate, XML_Parse/XML_ParseBuffer and XML_ParserFree calls must be made during this call. After XML_ExternalEntityParserCreate has been called to create the parser for the external parameter entity (context must be 0 for this call), it is illegal to make any calls on the old parser until XML_ParserFree has been called on the newly created parser. If the library has been compiled without support for parameter entity parsing (ie without XML_DTD being defined), then XML_SetParamEntityParsing will return 0 if parsing of parameter entities is requested; otherwise it will return non-zero. */

int XMLPARSEAPI XML_SetParamEntityParsing(XML_Parser parser, enum XML_ParamEntityParsing parsing);

enum XML_Error { XML_ERROR_NONE, XML_ERROR_NO_MEMORY, XML_ERROR_SYNTAX, XML_ERROR_NO_ELEMENTS, XML_ERROR_INVALID_TOKEN, XML_ERROR_UNCLOSED_TOKEN, XML_ERROR_PARTIAL_CHAR, XML_ERROR_TAG_MISMATCH, XML_ERROR_DUPLICATE_ATTRIBUTE, XML_ERROR_JUNK_AFTER_DOC_ELEMENT, XML_ERROR_PARAM_ENTITY_REF, XML_ERROR_UNDEFINED_ENTITY, XML_ERROR_RECURSIVE_ENTITY_REF, XML_ERROR_ASYNC_ENTITY, XML_ERROR_BAD_CHAR_REF, XML_ERROR_BINARY_ENTITY_REF, XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF, XML_ERROR_MISPLACED_XML_PI, XML_ERROR_UNKNOWN_ENCODING, XML_ERROR_INCORRECT_ENCODING, XML_ERROR_UNCLOSED_CDATA_SECTION, XML_ERROR_EXTERNAL_ENTITY_HANDLING, XML_ERROR_NOT_STANDALONE, XML_ERROR_UNEXPECTED_STATE };

/* If XML_Parse or XML_ParseBuffer have returned 0, then XML_GetErrorCode returns information about the error. */

enum XML_Error XMLPARSEAPI XML_GetErrorCode(XML_Parser parser);

/* These functions return information about the current parse location. They may be called when XML_Parse or XML_ParseBuffer return 0; in this case the location is the location of the character at which the error was detected. They may also be called from any other callback called to report some parse event; in this the location is the location of the first of the sequence of characters that generated the event. */

int XMLPARSEAPI XML_GetCurrentLineNumber(XML_Parser parser); int XMLPARSEAPI XML_GetCurrentColumnNumber(XML_Parser parser); long XMLPARSEAPI XML_GetCurrentByteIndex(XML_Parser parser);

/* Return the number of bytes in the current event. Returns 0 if the event is in an internal entity. */

int XMLPARSEAPI XML_GetCurrentByteCount(XML_Parser parser);

/* If XML_CONTEXT_BYTES is defined, returns the input buffer, sets the integer pointed to by offset to the offset within this buffer of the current parse position, and sets the integer pointed to by size to the size of this buffer (the number of input bytes). Otherwise returns a null pointer. Also returns a null pointer if a parse isn't active.

NOTE: The character pointer returned should not be used outside the handler that makes the call. */


const char XMLPARSEAPI * XML_GetInputContext(XML_Parser parser, int *offset, int *size);

/* For backwards compatibility with previous versions. */ #define XML_GetErrorLineNumber XML_GetCurrentLineNumber #define XML_GetErrorColumnNumber XML_GetCurrentColumnNumber #define XML_GetErrorByteIndex XML_GetCurrentByteIndex

/* Frees memory used by the parser. */ void XMLPARSEAPI XML_ParserFree(XML_Parser parser);

/* Returns a string describing the error. */ const XML_LChar XMLPARSEAPI * XML_ErrorString(int code);

/* Return a string containing the version number of this expat */ const XML_LChar XMLPARSEAPI * XML_ExpatVersion();

#ifdef __cplusplus } #endif

#endif /* not XmlParse_INCLUDED */

Currently browsing [xml.zip] (66,316 bytes) - [xml.cpp] - (8,079 bytes)

#include <stdlib.h>

#include "expat.h" #include "xml.h"

/** ****************************************************************************** * XmlNode implementation. ****************************************************************************** */

XmlNode::~XmlNode() { // Clear parent pointer from childs. for (XmlNodes::const_iterator it = m_childs.begin(); it != m_childs.end(); ++it) { (*it)->m_parent = 0; } }

bool XmlNode::isTag( const String &tag ) const { return stricmp( tag.c_str(),m_tag.c_str()) == 0; }

String XmlNode::getAttribute( const String &key ) const { XmlAttribute a; a.key = key; XmlAttributes::const_iterator it = m_attributes.find(a); if (it != m_attributes.end()) { return it->value; } return ""; }

bool XmlNode::haveAttribute( const String &key ) const { XmlAttribute a; a.key = key; XmlAttributes::const_iterator it = m_attributes.find(a); if (it != m_attributes.end()) { return true; } return false; }

void XmlNode::setAttribute( const String &key,const String &value ) { XmlAttribute a; a.key = key; a.value = value; m_attributes.insert(a); }

XmlNodeRef XmlNode::findChild( const String &tag ) const { for (XmlNodes::const_iterator it = m_childs.begin(); it != m_childs.end(); ++it) { if ((*it)->isTag(tag)) { return *it; } } return 0; }

//! Adds new child node. void XmlNode::addChild( const XmlNodeRef &node ) { assert( node != 0 ); m_childs.push_back(node); node->m_parent = this; };

//! Get XML Node child nodes. XmlNodeRef XmlNode::getChild( int i ) const { assert( i >= 0 && i < m_childs.size() ); return m_childs[i]; }

void XmlNode::getValue( String &value ) const { value = m_content; }

void XmlNode::getValue( int &value ) const { value = atoi(m_content.c_str()); }

void XmlNode::getValue( float &value ) const { value = atof(m_content.c_str()); }

void XmlNode::setValue( const String &value ) { m_content = value; }

void XmlNode::setValue( int value ) { char str[128]; itoa( value,str,10 ); m_content = str; }

void XmlNode::setValue( float value ) { char str[128]; sprintf( str,"%f",value ); m_content = str; }

bool XmlNode::getSubNodeValue( const String &tag,String &value ) const { XmlNodeRef node = findChild( tag ); if (node) { node->getValue( value ); return true; } return false; } bool XmlNode::getSubNodeValue( const String &tag,int &value ) const { XmlNodeRef node = findChild( tag ); if (node) { node->getValue( value ); return true; } return false; } bool XmlNode::getSubNodeValue( const String &tag,float &value ) const { XmlNodeRef node = findChild( tag ); if (node) { node->getValue( value ); return true; } return false; }

void XmlNode::setSubNodeValue( const String &tag,const String &value ) { XmlNodeRef node = findChild( tag ); if (!node) { node = new XmlNode( tag ); addChild( node ); } node->setValue( value ); } void XmlNode::setSubNodeValue( const String &tag,int value ) { XmlNodeRef node = findChild( tag ); if (!node) { node = new XmlNode( tag ); addChild( node ); } node->setValue( value ); } void XmlNode::setSubNodeValue( const String &tag,float value ) { XmlNodeRef node = findChild( tag ); if (!node) { node = new XmlNode( tag ); addChild( node ); } node->setValue( value ); }

String XmlNode::getXML() const { String xml;

// Begin Tag if (m_attributes.empty()) { xml = "<" + m_tag + ">"; } else { xml = "<" + m_tag + " ";

// Put attributes. for (XmlAttributes::const_iterator it = m_attributes.begin(); it != m_attributes.end(); ++it) { xml += it->key+"=\""+it->value+"\""; } if (m_content.empty() && m_childs.empty()) { // Compact tag form. xml += "/>\n"; return xml; } xml += ">"; }

// Put node content. xml += m_content;

if (!m_childs.empty()) { xml += "\n"; }

// Put sub nodes. for (XmlNodes::const_iterator it = m_childs.begin(); it != m_childs.end(); ++it) { xml += (*it)->getXML(); }

// End tag. xml += "</" + m_tag + ">\n"; return xml; }

/** ****************************************************************************** * XmlParserImp class. ****************************************************************************** */ class XmlParserImp { public: XmlParserImp(); XmlNodeRef parse( const std::vector<char> &buffer,String &errorString );

protected: void onStartElement( const char *tagName,const char **atts ); void onEndElement( const char *tagName ); void onRawData( const String& data );

static void startElement(void *userData, const char *name, const char **atts) { ((XmlParserImp*)userData)->onStartElement( name,atts ); } static void endElement(void *userData, const char *name ) { ((XmlParserImp*)userData)->onEndElement( name ); } static void characterData( void *userData, const char *s, int len ) { char str[32768]; assert( len < 32768 ); strncpy( str,s,len ); str[len] = 0; ((XmlParserImp*)userData)->onRawData( str ); }

// First node will become root node. std::vector<XmlNodeRef> nodeStack; XmlNodeRef m_root;

XML_Parser m_parser; };

/** ****************************************************************************** * XmlParserImp ****************************************************************************** */ XmlParserImp::XmlParserImp() { m_root = 0; }

void XmlParserImp::onStartElement( const char *tagName,const char **atts ) { XmlNodeRef parent; XmlNodeRef node( tagName );

if (!nodeStack.empty()) { parent = nodeStack.back(); } else { m_root = node; } nodeStack.push_back(node);

if (parent) { parent->addChild( node ); }

node->setLine( XML_GetCurrentLineNumber( (XML_Parser)m_parser ) ); // Call start element callback. String key,value; int i = 0; while (atts[i] != 0) { node->setAttribute( atts[i],atts[i+1] ); i += 2; } }

void XmlParserImp::onEndElement( const char *tagName ) { assert( !nodeStack.empty() ); if (!nodeStack.empty()) { nodeStack.pop_back(); } }

void XmlParserImp::onRawData( const String& data ) { assert( !nodeStack.empty() ); if (!nodeStack.empty()) { XmlNode *node = nodeStack.back(); node->setValue( data ); } }

XmlNodeRef XmlParserImp::parse( const std::vector<char> &buffer,String &errorString ) { m_parser = XML_ParserCreate(NULL);

XML_SetUserData( m_parser, this ); XML_SetElementHandler( m_parser, startElement,endElement ); XML_SetCharacterDataHandler( m_parser,characterData );

XmlNodeRef root = 0;

/* int size = file->size(); char *buf = (char*)memory::malloc( size ); file->read( buf,size ); if (!XML_Parse( parser,buf,size,1 )) { error( "XML Error (%s): %s at line %d\n",filename.c_str(),XML_ErrorString(XML_GetErrorCode(parser)),XML_GetCurrentLineNumber(parser) ); return false; } memory::free( buf );

XMLParser::parse( fileName ); */
if (XML_Parse( m_parser,buffer.begin(),buffer.size(),1 )) { root = m_root; } else { char str[32768]; sprintf( str,"XML Error: %s at line %d",XML_ErrorString(XML_GetErrorCode(m_parser)),XML_GetCurrentLineNumber(m_parser) ); errorString = str; } XML_ParserFree( m_parser );

m_root = 0;

return root; }

//! Parse xml file. XmlNodeRef XmlParser::parse( const String& fileName ) { m_errorString = ""; XmlParserImp xml; std::vector<char> buf; FILE *file = fopen( fileName.c_str(),"rb" ); if (file) { fseek( file,0,SEEK_END ); int fileSize = ftell(file); fseek( file,0,SEEK_SET ); buf.resize( fileSize ); fread( buf.begin(),fileSize,1,file ); fclose(file); return xml.parse( buf,m_errorString ); } else { return XmlNodeRef(); } } //! Parse xml from memory buffer. XmlNodeRef XmlParser::parse( const std::vector<char> &buffer ) { m_errorString = ""; XmlParserImp xml; return xml.parse( buffer,m_errorString ); };

Currently browsing [xml.zip] (66,316 bytes) - [xml.h] - (8,147 bytes)

#ifndef __XML_HEADER__
#define __XML_HEADER__

#include <string> #include <vector> #include <set>

typedef std::string String;

/**

This is wrapper arround expat library to provide DOM type of access for xml. Do not use XmlNode class directly instead always use XmlNodeRef wrapper that takes care of memory managment issues.

Usage Example: ------------------------------------------------------- void testXml() { XmlParser xml; XmlNodeRef root = xml.parse( "test.xml" );

if (root) { for (int i = 0; i < root->getChildCount(); i++) { XmlNodeRef child = root->getChild(i); if (child->isTag("world")) { if (child->getAttribute("name") == "blah") { } } } } }; */


/** ****************************************************************************** * XmlAttribute class ****************************************************************************** */

class XmlAttribute { public: String key; String value; XmlAttribute() {} XmlAttribute( const XmlAttribute &attr ) { *this = attr; } XmlAttribute& operator=( const XmlAttribute &attr ) { key = attr.key; value = attr.value; return *this; } bool operator<( const XmlAttribute &attr ) const { return stricmp( key.c_str(),attr.key.c_str() ) < 0; } bool operator==( const XmlAttribute &attr ) const { return stricmp( key.c_str(),attr.key.c_str() ) == 0; } bool operator!=( const XmlAttribute &attr ) const { return !(*this == attr); } };

class XmlNode;

//! Xml node attributes class. typedef std::set<XmlAttribute> XmlAttributes;

/** ****************************************************************************** * XmlNodeRef, wrapper class implementing reference counting for XmlNode. ****************************************************************************** */ class XmlNodeRef { private: XmlNode* p; public: XmlNodeRef() : p(NULL) {} XmlNodeRef( int Null ) : p(NULL) {} XmlNodeRef( XmlNode* p_ ); XmlNodeRef( const XmlNodeRef &p_ ); explicit XmlNodeRef( const String &tag ); ~XmlNodeRef(); operator XmlNode*() const { return p; } operator const XmlNode*() const { return p; } XmlNode& operator*() const { return *p; } XmlNode* operator->(void) const { return p; } XmlNodeRef& operator=( XmlNode* newp ); XmlNodeRef& operator=( const XmlNodeRef &newp ); operator bool() const { return p != NULL; }; bool operator !() const { return p == NULL; }; // Misc compare functions. bool operator == ( const XmlNode* p2 ) const { return p == p2; }; bool operator != ( const XmlNode* p2 ) const { return p != p2; }; bool operator < ( const XmlNode* p2 ) const { return p < p2; }; bool operator > ( const XmlNode* p2 ) const { return p > p2; }; friend bool operator == ( const XmlNodeRef &p1,int null ); friend bool operator != ( const XmlNodeRef &p1,int null ); friend bool operator == ( int null,const XmlNodeRef &p1 ); friend bool operator != ( int null,const XmlNodeRef &p1 ); };

/************************************************************************/ /* XmlParser class, Parse xml and return root xml node if success. */ /************************************************************************/ class XmlParser { public: //! Parse xml file. XmlNodeRef parse( const String& fileName ); //! Parse xml from memory buffer. XmlNodeRef parse( const std::vector<char> &buffer );

String getErrorString() const { return m_errorString; } private: String m_errorString; };

/** ****************************************************************************** * XmlNode class * Never use XmlNode directly instead use reference counted XmlNodeRef. ****************************************************************************** */

class XmlNode { public: //! Non virtual destructor, XmlNode cannot be used as a base class. ~XmlNode();

//! Get XML node tag. const String& getTag() const { return m_tag; };

//! Return true if givven tag equal to node tag. bool isTag( const String &tag ) const;

//! Get XML Node attributes. const XmlAttributes& getAttributes() const { return m_attributes; }; //! Get XML Node attribute for specified key. String getAttribute( const String &key ) const; //! Check if attributes with specified key exist. bool haveAttribute( const String &key ) const;

//! Set new XML Node attribute (or override attribute with same key). void setAttribute( const String &key,const String &value ); //! Adds new child node. void addChild( const XmlNodeRef &node );

//! Get number of child XML nodes. int getChildCount() const { return m_childs.size(); }; //! Get XML Node child nodes. XmlNodeRef getChild( int i ) const;

//! Find node with specified tag. XmlNodeRef findChild( const String &tag ) const;

//! Get parent XML node. XmlNodeRef getParent() const { return m_parent; }

//! Returns content of this node. const String& getContent() const { return m_content; };

//! Returns line number for XML tag. int getLine() const { return m_line; }; //! Set line number in xml. void setLine( int line ) { m_line = line; };

//! Returns XML of this node and sub nodes. String getXML() const;

//! Get value of node. void getValue( String &value ) const; void getValue( int &value ) const; void getValue( float &value ) const; void getValue( bool &value ) const { int v; getValue(v); value = (v != 0); }

//! Set value of node. void setValue( const String &value ); void setValue( int value ); void setValue( float value );

//! Get value of sub node. bool getSubNodeValue( const String &tag,String &value ) const; bool getSubNodeValue( const String &tag,int &value ) const; bool getSubNodeValue( const String &tag,float &value ) const;

//! Set value of sub node (Create sub node if neccesarry). void setSubNodeValue( const String &tag,const String &value ); void setSubNodeValue( const String &tag,int value ); void setSubNodeValue( const String &tag,float value );

private: //! The only ctor and private, protect us from deriviation. XmlNode( const String &tag ) { m_tag = tag; m_parent = 0; m_refCount = 0; }

//! Reference counting. void addRef() { m_refCount++; }; //! When ref count reach zero XML node dies. void release() { if (--m_refCount <= 0) delete this; };

//! Ref count itself, its zeroed on node creation. int m_refCount;

//! Line in XML file where this node firstly appeared (usefull for debuggin). int m_line; //! Tag of XML node. String m_tag;

//! Content of XML node. String m_content; //! Parent XML node. XmlNode *m_parent; //! Next XML node in same hierarchy level. typedef std::vector<XmlNodeRef> XmlNodes; XmlNodes m_childs; //! Xml node attributes. XmlAttributes m_attributes;

//! Lets be friendly to him. friend class XmlNodeRef; };

/////////////////////////////////////////////////////////////////////////////// // Inline Implementation of XmlNodeRef inline XmlNodeRef::XmlNodeRef( const String &tag ) { p = new XmlNode( tag ); p->addRef(); }

inline XmlNodeRef::XmlNodeRef( XmlNode* p_ ) : p(p_) { if (p) p->addRef(); }

inline XmlNodeRef::XmlNodeRef( const XmlNodeRef &p_ ) : p(p_.p) { if (p) p->addRef(); }

inline XmlNodeRef::~XmlNodeRef() { if (p) p->release(); }

inline XmlNodeRef& XmlNodeRef::operator=( XmlNode* newp ) { if (newp) newp->addRef(); if (p) p->release(); p = newp; return *this; }

inline XmlNodeRef& XmlNodeRef::operator=( const XmlNodeRef &newp ) { if (newp.p) newp.p->addRef(); if (p) p->release(); p = newp.p; return *this; }

inline bool operator == ( const XmlNodeRef &p1,int null ) { return p1.p == 0; }

inline bool operator != ( const XmlNodeRef &p1,int null ) { return p1.p != 0; }

inline bool operator == ( int null,const XmlNodeRef &p1 ) { return p1.p == 0; }

inline bool operator != ( int null,const XmlNodeRef &p1 ) { return p1.p != 0; }

#endif // __XML_HEADER__

Currently browsing [xml.zip] (66,316 bytes) - [xmlmain.cpp] - (253 bytes)

#include "xml.h"

void printXml( XmlNodeRef node ) { String str = node->getXML(); printf( "%s",str.c_str() ); }

void main() { XmlParser xmlParser; XmlNodeRef root = xmlParser.parse( "test.xml" );

if (root) { printXml( root ); } }

The zip file viewer built into the Developer Toolbox made use of the zlib library, as well as the zlibdll source additions.

 

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